1. Field of the Invention
This invention relates to a coaxial type composite loudspeaker, and more particularly to a coaxial type composite loudspeaker comprising at least three coaxially arranged loudspeaker of different allocated frequency bands.
2. Description of the Prior Art
A conventionally known three-way compound loudspeaker has a construction in which a loudspeaker responsive only to the intermediate acoustic frequencies and used for reproducing sounds of intermediate pitch (hereinafter referred to as a "squawker") and a loudspeaker responsive only to the high acoustic frequencies and used for reproducing sounds of high pitch (hereinafter referred to as a "tweeter") are disposed through a spacer on the top portion of the center pole of a loudspeaker responsive only to the low acoustic frequencies and used for reproducing sounds of low pitch (hereinafter referred to as a "woofer") and are arranged in a row above the opening of the woofer, a construction in which a woofer has a bridge built on the frame thereof and a squawker and a tweeter are attached to the surface of the bridge and arranged in a row and flush with each other, or in which a woofer is provided on the rear surface of its grilled with a squawker and a tweeter which are arranged in a row.
In all of the constructions described above, however, the squawker and the tweeter obstruct the greater part of the opening of the woofer and consequently the opening area of the woofer is made narrow which prevents the radiation of sounds. This adversely affects the quality of sound and the frequency characteristics. Further, since the sound sources cannot be centralized, the localization of the sound image is shifted and the directional characteristics on the horizontal plane are apt to vary. Furthermore, since the squawker and the tweeter are arranged in a row in the opening of the woofer, the sizes of the squawker and the tweeter are limited. This imposes restrictions on the degree of freedom of designing a speaker system, necessitates changing the cone paper of the woofer into a special shape in order to prevent the squawker and the tweeter from colliding against the cone surface of the woofer, and reduces the quality of sound. Thus, the conventional compound loudspeakers entail a number of problems to be technically solved.